How do I check out a 3.0 cis engine

[rgmrgm]

I bought a 78 3.0 engine complete w/cis, ignition and alternator. History unknown but supposedly was removed while in good running condition several years ago. no obvious sign of leaks, bottom is covered with road grime so it had not been cleaned up. oil return tubes had been replaced with expansion type tubes. I have a 77 coupe with a bad engine also a 78 3.0. I want to swap the engines. I have it on an engine stand and have turned it over by hand. i also removed two broken exhaust studs. i have removed the valve covers and found no broken head studs. compression test does not work well just turning it over with a wrench. is there any way to bench test the cis system. should i just stick it in the car and see what happens or what should i do to verify engine condition prior to installation.

[dad911]

You could do a leakdown test, but it may be misleading since the engine hasn't been run. You would need to connect a starter to do a compression test.

I'd probably cross my fingers, put it in and hope for the best.

[snbush67]

The compression test is the way to go. Please describe what is not working for you? Can you hear or feel air leaking from the exhaust or intake?

[T77911S]

short of putting it in the car...leak down test.

[Groesbeck Hurricane]

while it is on your stand, go through the CIS and check the rubber to ensure it is in good order.

Use a bendable light or bright light and a mirror and look behind your fan to ensure nothing has made a nest inside.

Were the oil intakes blocked off?

While it is on the stand, change the plugs and look into the cylinders to see if all "appears" OK.

If it were me, I would, while still on the stand, adjust all the valves and replace the gaskets with the re-useable ones if they are not already. Remember DO NOT overtorque the valve covers. Verify the oil sensors do not appear to have leaked (easier to change while on stand). Clean as much grime as possible.

I'm hoping for the best as well!!! Sometimes, these things work out very well!

[Groesbeck Hurricane]

OH, And the engine appears to be missing the tin to seal the top of the engine away from the road. I am assuming you have this?

And, I would also put assembly lube where I could when I took off the valve covers. Can't hurt anything...

[WPOZZZ]

Looks like it has Carrera tensioners.

[914efi]

Check to see if it has steel lower head studs. If they are original dilivar and it has been sitting, you should assume several of them will break once it goes through heat/stress cycles. They could have been replaced with dilivar, steels have been more recent practice. I would put it in to make sure all else is good, and then plan on taking it out once this needs to be done. Dilivar already are non magnetic, easy to test.

Chances are good that the fuel dist will need attention. You can put fuel pressure into the system, pull all injectors and put into jars and then lift the air plate to see that they all flow about equally.

[rgmrgm]

NEVER MIND, checked the torque on head studs one snapped at 20 pounds. porsche should get nailed for these defective head studs i have three 911 SC's all have experienced broken head studs

[boyt911sc]

Where are you located? I have an engine test stand specially designed for CIS engines that is available for the next few months.

Tony